Monday, October 08, 2012

How Spacey is Outer Space?

Yesterday I was quickly in and out of a bookstore and while there I leafed through Richard Dawkins's new book called The Magic of Reality. It has a killer subtitle -- How We Know What's Really True. On the cover, Philip Pullman calls it "The clearest and most beautifully written introduction to science I've ever read."I saw something there that was so profound, and presented in such a memorably analogous fashion that I am going to paraphrase it here, for y'all. And hopefully, you will be able to always remember it, too.Here goes -- first, picture an empty football field.Are you there?OK -- now go and plunk down a football in the very middle, at the 50 yard line. That football represents our sun.Now, get this -- to illustrate the scale of…. "reality" -- walk away from the football and place a peppercorn 25 metres distant. This is the relative size and distance our Earth is from the sun. Our moon would be the size of the head of a pin, and be placed just 5 centimetres from the peppercorn.But here's the incredible thing -- the NEAREST star to our own sun, Proxima Centauri, would be placed 6,500 kilometres distant.

That just boggles my mind. I mean, think of it, that would be the nearest star to us, of all the millions of visible stars in our night sky. Proxima Centauri is a mere 4.2 light years away from our sun. But the furthest star that we currently know about [V12, in the galaxy NGC4203] is 10.4 million light years away, [hmmm… how much is that in football fields?]… and estimated to be 10 million times brighter than our own sun. I look forward to the launch of the James Webb infrared telescope, which will make the Hubble seem like a regular pair of binoculars. We will be seeing pretty much infinitely further than we have ever seen before, or as some scientists are referring to it, "the very beginnings of time itself."Cheers!*****